Eur. Phys. J. E 7, 83-93 (2002)
Chiral electrostatic interaction and cholesteric liquid crystals of DNAA.A. Kornyshev1, S. Leikin2 and S.V. Malinin1, 3
1 Forschungszentrum Jülich, D-52425, Jülich, Germany
2 NICHD, National Institutes of Health, Bethesda, Maryland 20892, USA
3 L.D. Landau Institute for Theoretical Physics, RAS, 117940, Kosygina 2, Moscow, Russia
(Received 31 October 2001)
Explicit expressions for electrostatic interaction between stiff DNA duplexes of finite length are obtained. These expressions allow for the helical symmetry of charge distribution on DNA molecules and reveal chiral and non-chiral interaction terms. Asymptotic expressions at small twist angles are applied to evaluate the cholesteric pitch and the twist elastic constant and their dependence on the length of DNA fragments. These estimates suggest an explanation for the large value of the cholesteric pitch and its nonmonotonic variation with the density of the liquid crystal. An analysis of biaxial correlations rationalizes the driving force of the transition from the cholesteric to hexagonal phase upon dehydration.
61.30.Cz - Molecular and microscopic models and theories of liquid crystal structure.
64.70.Md - Transitions in liquid crystals.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2002